Microelectronic arrays utilizing electric field transport have been developed for DNA diagnostics (including infectious and genetic disease and cancer detection), for short tandem repeat (STR) forensics analysis, and for gene expression applications. In addition to these bioresearch and clinical diagnostic applications, such devices also have the potential to carry out the assisted assembly of a wide variety of molecular scale, nanoscale and microscale components into higher order structures. These microelectronic array devices are able to produce defined electric fields on their surfaces that allow molecules and other entities with high fidelity recognition properties to be transported to or from any site on the surface of the array. Such devices can utilize either DC electric fields which cause movement of entities by their relative charge, or AC electric fields which allow entities to be selectively positioned by their dielectric properties. An almost unlimited variety of molecules and nanocomponents can be utilized with these devices, including: DNA, DNA constructs with fluorescent, photonic or electronic transfer properties, RNA, RNA constructs, amino acids, peptides, proteins (antibodies, enzymes), nanoparticles (quantum dots, carbon nanotubes, nanowires), cells and even micron scale semiconductor components. Thus, electric field devices can be used for developing a unique highly parallel “Pick & Place” fabrication process by which a variety of heterogeneous molecules, nanocomponents and micron sized objects with intrinsic self-assembly properties can be organized into higher order 2D and 3D structures and devices. The process represents a unique synergy of combining the best aspects of a “top-down” process with a “bottom-up” process. Finally, integration of optical tweezers for manipulation of live cells and microspheres in a similar microarray setup is demonstrated for the applications of biological delivery and invasive manipulation of these species.